Economic development is necessary if we want to improve society. There comes a time     1     the old must give way to the new.     2     (keep) the right balance between progress and the protection of cultural sites can be a big challenge. Big challenges, however, can sometimes lead to great     3     (solve). In order to benefit the area, the Egyptian government wanted to build a new dam     4     the Nile. But the     5     (propose) led to protests. Later, a committee       6     (establish) to limit damage to the Egyptian buildings and prevent the     7     (lose) of cultural relics. Temples and other cultural sites were taken down piece by piece, and then moved and put back together again in a place     8     they were safe from the water. When the project     9     (end) in 1980, it was considered     10     great success.